This invention relates to certain therapeutic polypeptides useful in man and animals. Specifically, the therapeutic polypeptides are useful in cases of intra- and extracellular bacteria, fungi and protozoa which are either resistant to conventional antibiotics, difficult to treat without harm to the host cells, associated with severe infections, or connected with cases of traumatized or immune compromised hosts. In view of the properties of the therapeutic polypeptides of this invention which include definite antibacterial, anti-fungal and anti-protozoan activity, the therapeutic polypeptides provided herein are termed antimicrobial polypeptides.
Further, this invention relates to biosynthetic processes affording the antimicrobial polypeptides, including cloning or producing the desired polypeptides in various media, both as active antimicrobial polypeptides and also in the pro-form or the inactive antimicrobial polypeptide form with subsequent activation procedures. Included in these processes and procedures for biosynthesis of the antimicrobial polypeptides of this invention are novel forms of the polypeptides themselves, synthetic or semi-synthetic polypeptides and cells, containing such novel polypeptides which are themselves novel compositions, or cell lines, or hybridoma.
Still further, this invention relates to novel cells, including animal cells, and particularly mammalian cells, containing such antimicrobial polypeptides, including various specific mammalian cell types which contain the antimicrobial polypeptides. Methods for treating mammals infected with certain bacteria, protozoa, or fungi, and which are resistant to known antibiotics or which are difficult to treat with such antibiotics are also included in the present invention. As a novel composition, the present invention includes specifically mammalian cells having genes encoding for such antimicrobial polypeptides; particularly, various specific embryonic cells having the genes encoding for the antimicrobial polypeptides are included in the present invention. Additionally, processes for and methods of preparing mammalian cells including the genes encoding for antimicrobial polypeptides of this invention using recombinant DNA techniques are a part of the present invention.
A number of the antimicrobial polypeptides have been found to be useful when the genes encoding therefor are incorporated into various plant species. Particularly, when introduced into the plant genome by means of Agrobacterium, the antimicrobial polypeptide encoding genes produce plant species much more resistant to certain bacterially induced disease conditions and plant pathogens. Such antimicrobial polypeptides and the incorporation of the genes encoding therefor are more fully described in U.S. patent application Ser. No. 889,225, filed Jul. 25, 1986, to Jaynes et al, which is incorporated herein by reference as if fully set forth.
Although antimicrobial polypeptides of the type envisioned in the present invention are known from the humoral response to bacterial infection of the Hyalophora cecropia (a species of large silk moth), prior to the discovery of Jaynes et al, supra, it was unknown that such antimicrobial polypeptides were useful against plant pathogens or how the same could be transformed into plants. It is likewise previously unknown before the present invention, that the antimicrobial polypeptides would be similarly effective in animal, and particularly mammalian species, against certain microorganisms, or what method could be employed to transform cells of such species therewith.
It is known that certain polynucleotide molecules can be expressible in a given host and have the sequence araB promoter operably linked to a gene which is heterologous to such host. The heterologous gene codes for a biologically active polypeptide. A genetic construct of a first genetic sequence coding for cecropin operably linked to a second genetic sequence coding for a polypeptide which is capable of supressing the biological effect of the resulting fusion protein towards an otherwise cecropin-sensitive bacterium, International Patent Publication W086/04356, Jul. 31, 1986.
It is therefore an object of the present invention to provide antimicrobial polypeptides for therapeutic treatment of pathogens in mammals including bacteria, fungi, and protozoa. A further object is to provide a method for treatment of man and animals having a bacterial infection with an antimicrobial polypeptide for such infection. A still further object of the present invention is to provide for a biosynthetic process to produce such antimicrobial polypeptides. Another object of the present invention is to provide for novel synthetic and semisynthetic antimicrobial polypeptides produced by recombinant DNA procedures. A still further object of the invention provides cells from a host animal transformed by genetic sequences incorporated into the cells, and ultimately to provide transformed animals which are as a result resistant to a number of pathogenic microorganisms.
These and still other objects of the invention are provided according to the present invention as described in the following specification.